Minister for marketing and animal husbandry C Adinarayana Reddy warned of stringent action against the users of antibiotics in aqua culture. Reviewing aqua culture activities with the officials and the farmers associations at Velagapudi on Wednesday, the minister asked them to issue licences registering aqua forms officially. He said the government would construct five fishing harbours at a cost of Rs 1,500 crore in the state. Already, the works were going on at Antarvedi, he said. The state enjoys top position in aqua culture by exporting prawns worth Rs 20,000 crore and the fish worth Rs 40,000 crore to various countries. The state government has the responsibility to ensure quality of aqua products while exporting, he said. All the fish tanks should be registered, he said, and asked the officials to take action against illegal aqua cultivation anywhere in the state. He directed the fisheries officials to set up a joint committee with marine export authority. On the occasion, the representatives of farmers said that Ecuador in South America has been cultivating fish for quite some time without using antibiotics. They asked the government to explore the possibilities to get support from cuador.